中文摘要：

考虑诊断中性束在HT-7等离子体中的电离，复合和电荷交换，对不同靶等离子体的等离子体温度、密度和杂质含量，计算了中性束在等离子体中的衰减。分析结果表明，等离子体的密度对中性束的衰减影响较大，而温度的变化对中性束衰减影响较小。当增大时，中性束衰减率随等离子体密度显著增大；当中性束的能量增大时，中性束也衰减较甚。含杂质中性束的衰减率也增大。最后，根据诊断中性束在EAST托卡马克中等离子体衰减的计算结果，给出了EAST托卡马克中等离子体所要求的诊断中性束参数。

英文摘要：

In this work, attenuation of the injected diagnostic neutral beam in different electron temperatures, electron densities, and impurity concentrations of the target plasma in HT-7 tokamak was calculated by considering effects of the three basic atomic processes, i.e. ionization, recombination and charge-exchange. The results show that the attenuation depends strongly on the plasma density and beam energy, but the plasma temperature has less effect. The attenuation of the diagnostic neutral beam in the EAST plasma has been estimated based on the same principle, and the required parameters for the EAST diagnostic neutral beam are given as well.